[Committed] S/390: z10 no need to optimize FP compares

[Andreas Krebbel]

Hi,

the attached patch prevents machine dependent reorg to rework non-int
mode compares.  The bypass conflict problem occurs only in the integer
pipeline since the other pipelines are anyway single issue.

Tested with --with-arch=z10 - no regressions.

Applied to mainline and 4.4 branch.

Bye,

-Andreas-


2009-10-19  Andreas Krebbel  <Andreas.Krebbel@de.ibm.com>

	* config/s390/s390.c (s390_z10_optimize_cmp): Don't touch FP compares.


Index: gcc/config/s390/s390.c
===================================================================
--- gcc/config/s390/s390.c.orig	2009-10-19 09:35:56.000000000 +0200
+++ gcc/config/s390/s390.c	2009-10-19 09:36:25.000000000 +0200
@@ -9864,6 +9864,9 @@ s390_z10_optimize_cmp (rtx insn)
   if (!REG_P (*op0) || !REG_P (*op1))
     return false;
 
+  if (GET_MODE_CLASS (GET_MODE (*op0)) != MODE_INT)
+    return false;
+
   /* Swap the COMPARE arguments and its mask if there is a
      conflicting access in the previous insn.  */
   prev_insn = prev_nonnote_insn (insn);